Parched California hunts for water in unusual places

DEATHLY dry is the new normal in California. As of 27 January, snowpack in the Sierra Nevada mountains, which usually supplies a third of California's water, stood at just 12 per cent of normal levels. And those who track moisture in the state say that climate change will cause more precipitation to fall as rain – and over shorter periods – meaning dramatic measures will be necessary to slake the thirst of its population of 38 million.

This is indicative of California's future climate under certain greenhouse conditions, says Heather Cooley of the Pacific Institute, an environmental research group in Oakland, California. "If you look at the projections towards the end of the century, that's our average."

To respond to the longer periods of dryness, state and local officials are assessing ways to wring water from traditionally overlooked sources.

The Santa Clara Valley Water District, for example, is building a waste water treatment plant that will produce 30 million litres of clean water a day when it opens this year.

And in July, Mark Hanna, a water engineer working in Los Angeles, will punch holes in the city's concrete skin and turn them into wells that will gather precious storm water before it runs off into the Pacific Ocean.

Desalination is on the table, too. The Carlsbad Project in San Diego county will deliver treated seawater to the region and is due to open in 2016. The plant's website describes the supply as drought-proof – exactly what California desperately needs.

This article appeared in print under the headline "California's big thirst"

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There was no need for the floodgates at Folsom dam, California, on Sunday (Image: Ken James/Bloomberg/Getty)